Transcription of Crystallization is used to purify a solid. The process ...
{{id}} {{{paragraph}}}
Example: quiz answers
Crystallization is used to purify a solid. The process ...
Crystallization is used to purify a solid. The process requires a suitable solvent. Asuitable solvent is one which readily dissolves the solid (solute) when the solvent is hotbut not when it is cold. The best solvents exhibit a large difference in solubility over areasonable range of temperatures. (eg, Water can be a Crystallization solvent between0-100oC; hydrocarbon solvents such as hexanes or petroleum ether have a different Trange since they can be cooled below 0 degrees but boil below 100 degrees). Characteristics of a solvent:a. chosen for solubilizing power-- solubility usually increases with increasing Tb. polarity is important--like dissolves like; polar compounds are more soluble in polarsolvents; nonpolar compounds in nonpolar solventsc. should be INERT but few are; eg, acetic acid is sometimes used as a solventalthough it will certainly react with basic compoundsd. almost all solvents are COMBUSTABLE--avoid flamese. mixed solvents (eg; 1:1 water/methanol) provide a huge range of possible solventsbut they must be soluble in one anotherQ: Is 95% ethanol a mixed solvent?
behind) or filter. e. if filtering is necessary, do so to remove suspended solids, the faster the better, keep ... Another trick is to use a piece of cotton or glass wool loosely wedged into the cone of ... There are different methods used for heating material in the laboratory. Flames are never used in the laboratory except in controlled ...
Loading..
Tags:
Information
Domain:
Source:
Link to this page:
Please notify us if you found a problem with this document: